is it recommended to start with an MVC framework for wordpress?
Not really. WP has no native inclination or affinity for MVC.
tbh it’s hard to follow/understand plugins as each developer use his own style (most of time it’s like spaghetti coding)…
Welcome to WordPress. 🙂 Have no doubt though — people can mess up MVC just as thoroughly.
will a MVC framework make a plugin more maintenable.. are there limits/constraints of using the MVC approach in wp?
If you have knowledge and skills for specific approach then it would be easier and more convenient to maintain for you. And the other way around. There are very few universal conventions in WP development for code organization.